This is the bitmap data structure for the circular slider buttons.

typedef struct _CSBITMAPDATA {
  HBITMAP     hbmLeftUp;
  HBITMAP     hbmLeftDown;
  HBITMAP     hmbRightUp;
  HBITMAP     hbmRightDown;
} CSBITMAPDATA;

typedef   CSBITMAPDATA   * PCSBITMAPDATA ;